Researchers have discovered that serotonin present in the cerebellum plays a crucial role in the regulation of anxiety.
- High levels of serotonin in the cerebellum reduce anxious behavior in mice.
- The stimulation of serotonergic neurons in the cerebellum decreases anxiety, while their inhibition increases it.
- This discovery could help improve anxiety treatments.
A team, made up of researchers from the University of Pennsylvania and the Temasek Life Sciences Laboratory, has made a discovery that makes it possible to better understand the origin of anxiety. By studying mice, she noticed that serotonin present in the cerebellum (region of the brain involved in controlling the motor function and certain higher cognitive functions) regulates anxious behavior.
Anxiety: serotonin plays a brake role in the cerebellum
To check if the serotonin level in the cerebellum plays a role in anxious behavior, researchers have artificially stimulated or inhibits neurons producing hormone in mice. They then noticed that rodents with small quantities of cerebellar serotonin were more anxious. Conversely, animals that displayed a high level of serotonin in the cerebellum had less anxious behavior. Furthermore, scientists have noted that they could in a bidirectional way the level of mouse anxiety by artificially acting on hormone levels in the cerebellum.
Faced with these results, scientists conclude that serotonin present in the cerebellum acts as a brake of anxiety. “These results represent progress towards understanding how the cerebellum regulates anxiety behavior and provide new evidence of a functional connection between the cerebellum and the serotonin system within the anxiety circuit”they say.
Serotonin and cerebellum level: towards improving anxiety treatments
“This is the first analysis of the involvement of the neuromodulator, serotonin, in the cerebellum during anxious behavior. Our results reveal that serotonin regulates anxious behavior. This offers a new overview of the role of serotonin in the cerebellum, as well as the way the cerebellum interacts with the rest of the brain to produce anxiety“, write the authors in their article published on February 10, 2025 in the journal Journal of Neuroscience.
The team notes that this discovery could help improve the treatment of anxious disorders. “Our results are important for the future use of serotonin -related pharmacological therapies, such as selective serotonin reuptake inhibitors, in the treatment of anxiety in humans”she explains.
